Cod sursa(job #2618430)

Utilizator jungleTUDOSE MIHAI-CRISTIAN jungle Data 24 mai 2020 20:58:27
Problema Statistici de ordine Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.15 kb
#include <iostream>
#include <fstream>
#include <cstdlib>
using namespace std;

ifstream f("sdo.in");
ofstream g("sdo.out");

int v[3000002];
int normal_partition(int left,int right)
{
    int pivot,poz,i;
    poz = left;
    pivot = right;
    for(i=left; i<right; i++)
    {
        if(v[i] < v[pivot])
        {
            swap(v[i],v[poz]);
            poz++;
        }
    }
    swap(v[pivot],v[poz]);
    return poz;
}

int random_partition(int left,int right)
{
    int temp;
    if(right-left+1)
    {
        temp = left + rand() % (right - left + 1);
    }
    swap(v[right],v[temp]);
    return normal_partition(left,right);
}

int quickSelect(int left,int right,int k)
{
    int aux,temp;
    if(left==right)
    {
        return v[left];
    }
    aux = random_partition(left,right);
    temp = aux - left + 1;
    if(k <= temp)
    {
        return quickSelect(left,aux,k);
    }
    else
    {
        return quickSelect(aux + 1,right,k - temp);
    }
}

int main()
{
    int n,i,k;
    f>>n>>k;
    for(i=0; i<n; i++)
    {
        f>>v[i];
    }
    g<<quickSelect(0,n-1,k);

    return 0;
}